1. Field of the Invention
The present invention relates to a parking brake device allowing a vehicle to be maintained in a braking state during parking, and particularly to a parking brake device suitable for a small-sized vehicle having a simple structure allowing about one or two persons to ride thereon.
2. Description of Background Art
An automobile of a four-wheel or three-wheel type includes a parking brake device allowing a vehicle to be kept in a wheel braking state during parking or the like. In this parking brake device, a pull-up force of a parking lever provided in the vicinity of a driver""s seat is transmitted to a brake device via a brake wire, to lock a corresponding wheel.
A vehicle including an automatic transmission may use a device for starting an engine in a parking brake operational state. In a vehicle of this type, the engine can be started in a state in which wheels are locked.
In recent years, from the viewpoint of reducing the amount of exhaust gas and also reducing the power consumption, a small-sized vehicle allowing about one or two persons to ride thereon has been developed and practically used.
Such a small-sized vehicle includes an engine having a small displacement or an electric motor (or a combination of an engine and an electric motor), which vehicle is used as means allowing a small number of persons to be easily moved with a reduced fuel consumption and a reduced amount of exhaust gas.
As a small-sized vehicle of this type, there is known a small-sized vehicle described, for example, in Japanese Patent Laid-open No. Hei 9-286348.
This small-sized vehicle has a body structure including a body frame formed by a pipe made from metal such as aluminum, which frame is covered with a resin made body cover divided into two parts in the vertical direction, wherein the upper body cover constitutes a roof, the lower body cover constitutes a driver""s seat portion, and a body portion constitute a cabin for a single driver""s seat. From the viewpoint of reducing the weight of the vehicular body and the cost, and of simplifying the power source. Such a small-sized vehicle is often of a type in which a door or a roof is omitted for allowing a driver to easily get on and off the vehicle.
The above-described conventional device allows for the start-up of an engine in a wheel lock state and is characterized by detecting the fact that a select lever of a transmission is located at a parking position and a parking brake lever is pulled up by using an electric sensor, and controls the start-up of the engine by an ignition device. Such a device, however, has a disadvantage because it has a complicated and expensive structure. Accordingly, for a vehicle, particularly, a small-sized vehicle required to be reduced in weight and cost, it is expected to provide a parking brake device with a simple structure at a low cost.
For a vehicle, it is also expected to provide a parking brake device allowing a vehicle to be kept in a parking brake operational state when the vehicle is parked and the driver is separated from the vehicle.
For a vehicle with no roof or a small-sized vehicle with no door, since a parking brake lever provided in a driver""s seat is exposed, it is expected to provide a parking brake device not allowing the parking brake to be easily released in a state in which a driver is separated from a vehicle.
In view of the foregoing, the present invention has been made, and an object of the present invention is to provide a parking brake device having a simple structure allowing a vehicle to be maintained in a parking brake operational state when the vehicle is parked and the driver is separated from the vehicle.
Another object of the present invention is to provide a parking brake device having a simple structure allowing a vehicle to be maintained in a parking brake operational state when a power supply such as an internal combustion engine or an electric motor is started. Other objects will be more clearly understood in the following description.
To achieve the above objects, according to the present invention, there is provided a parking brake device for a vehicle, including a base member fixed on a vehicular body side of a portion, in the vicinity of a drive""s seat, of the vehicle; a parking lever movably supported by the base member; and a brake wire for transmitting a pull-up force of the parking lever thereby locking a brake device of a wheel. The parking lever is provided with an ignition device having a first position where a key is removably insertable in a key cylinder and a second position where a power supply of the vehicle becomes an operational state. The positions are set as shift positions of the key cylinder. The ignition device is provided with a lock piece, which projects when the key cylinder is located in the first position and retracts when the key cylinder is turned into the second position. The parking lever is provided with an engagement portion to be engaged with the lock piece in the projecting state, thereby fixing the parking lever; whereby the key is removably insertable in the key cylinder only in a state in which the parking brake device is operated.
With this configuration, the parking lever must be pulled up before the key cylinder is located at the first position. Accordingly, if the ignition key is removed from the key cylinder when the vehicle is parked and the driver is separated from the vehicle, the wheels are already in the lock state because of the parking brake. Also the key cylinder must be located in the first position before the ignition key is inserted in the key cylinder for starting a power supply such as an internal combustion engine of a vehicle in the parking state. Accordingly, if a power supply such as an internal combustion engine of a vehicle in the parking state is started, the parking lever is already in the pulled-up state and thereby the wheels are already in the lock state because of the parking brake.
In the parking brake device for a vehicle according to the present invention, preferably, the parking lever is provided with a cutout in which the lock piece in the projecting state is to be inserted; and a link mechanism having a stop plate for opening/closing the cutout according to the movement of the parking lever is interposed between the parking lever and the base member, the stop plate being operated to open the cutout for allowing the projection of the lock piece in a state in which the parking lever is pulled up and to block the cutout for blocking the projection of the lock piece in a state in which the parking lever is depressed.
With this configuration, it is possible to realize a parking brake mechanism operated in co-operation with the ignition device by using a simple structure capable of controlling the operation of the parking lever due to insertion/removal of the lock piece in/from the cutout and the presence and absence of engagement of the lock piece in the cutout by means of the stop plate of the link mechanism operated according to the movement of the parking lever.
In the parking brake device for a vehicle according to the present invention, preferably, the parking lever is provided with a cutout in which the lock piece in the projecting state is to be inserted; and a link mechanism having a stop plate for opening/closing the cutout according to the movement of the parking lever is interposed between the parking lever and the base member, the stop plate being operated to open the cutout for allowing the projection of the lock piece in a state in which the parking lever is pulled up and to block the cutout for blocking the projection of the lock piece in a state in which the parking lever is depressed.
With this configuration, it is possible to realize a parking brake mechanism operated in co-operation with the ignition device by using a simple structure capable of controlling the operation of the parking lever due to insertion/removal of the lock piece in/from the cutout and the presence and absence of engagement of the lock piece in the cutout by means of the stop plate of the link mechanism operated according to the movement of the parking lever.
In the parking brake device for a vehicle according to the present invention, preferably, a ratchet is provided on a vehicular body side and a pole lever having a claw to be engaged with the ratchet is turnably provided on the parking lever; the pole lever is provided with a stop plate portion, the stop plate portion being operated to open the cutout for allowing the projection of the lock piece in a state in which the parking lever is pulled up and to block the cutout for blocking the projection of the lock piece in a state in which the parking lever is depressed.
With this configuration, it is possible to realize a parking brake mechanism operated in co-operation with the ignition device by using a simple structure capable of controlling the operation of the parking lever due to insertion/removal of the lock piece in/from the cutout and the presence and absence of engagement of the lock piece in the cutout by means of the stop plate portion of the pole lever operated according to the movement of the parking lever.
The present invention is applicable to a vehicle including an internal combustion engine as a power supply, and to a vehicle including an electric motor as a power supply.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.